A traditional approach to annotate digital images is to manually annotate each digital image with one or more semantically related keywords. Such keywords are often used to facilitate keyword-based image search and retrieval operations in computer-based search environments (e.g., across computing devices, databases, the Internet, etc.). Because of the very large number of digital images that generally exist in such search environments, manual annotation of digital images to facilitate image search and retrieval operations represents a very labor intensive and time consuming task.